1. Field of the Invention
The present disclosure relates to a power apparatus, a power system, and a power control method.
2. Description of the Related Art
In recent years, power apparatuses, such as operation aiding equipment for aiding/acting for operations of physically-disabled people, the elderly, workers, and so on and robot suits for augmenting human muscle power have been developed (e.g., refer to “Robot Watch”, Internet URL: http://robot.watch.impress.co.jp/cda/news/2008/11/07/1427.html, searched on Nov. 24, 2009).
In terms of the weights of the apparatuses, the known power apparatuses are typically equipped with lightweight, small-capacity batteries. Examples of the batteries include lithium-ion batteries and nickel-hydrogen batteries.
However, since the operating time of small-capacity batteries provided in the known power apparatuses is short (e.g., one to three hours), the users often have to carry backup batteries with them. This is burdensome and inconvenient for the users.
Since the batteries used for the know power apparatuses are high in the internal resistance and are short in the life cycle, it has been practically difficult to charge the batteries with an energy source that temporarily generate electric power at high frequency.